[Observational and genetic epidemiological study on the association of alcohol consumption and chronic obstructive pulmonary disease in adults in 10 areas of China].

Objective: To investigate the associations between alcohol intake and risks of chronic obstructive pulmonary disease (COPD) using self-reported alcohol intake and genetically predicted mean alcohol intake in adults in 10 areas of China. Methods: This study used baseline data collected in 2004-2008 from the China Kadoorie Biobank, and the COPD outcome was determined through long-term follow-up. After excluding participants with cancer, coronary heart disease, stroke or transient ischemic attack, asthma, tuberculosis, or COPD at baseline, 445 523 participants were included in the observational analysis. A total of 133 168 participants with complete genotyping data were included in the genetic analysis, after the same exclusion criteria were applied. Alcohol consumption patterns were obtained through a baseline questionnaire. The mean alcohol intake of male non-abstainers was calculated based on the combination of ALDH2-rs671 and ADH1B-rs1229984 genotypes and the study region, and all participants were divided into six groups (C1-C6) accordingly. Cox proportional hazards regression models were used to estimate the associations between exposure factors and risk of incident COPD. Results: In the observational analysis, 11 825 incident cases of COPD were identified during an average follow-up period of (11.8±2.1) years. After adjusting for potential confounders, occasional and current drinking was associated with lower risk of incident COPD in males, with HRs (95%CIs) of 0.80 (0.74-0.86), 0.75 (0.68-0.83), 0.84 (0.76-0.93), 0.86 (0.76-0.97) and 0.84 (0.75-0.94) for occasional and current drinkers consuming pure alcohol <140.0, 140.0-, 280.0-, ≥420.0 g/week respectively, while there was no significant association between abstainers and risk of COPD. In females, compared with non-drinkers, the risk of COPD reduced in all groups except for current drinkers consuming pure alcohol 70.0-139.9 g/week, with HRs (95%CIs) of 0.81 (0.68-0.96), 0.87 (0.82-0.93), 0.78 (0.62-0.99) and 0.77 (0.62-0.96) for abstainers, occasional and current drinkers consuming pure alcohol <70.0, 70.0-, ≥140.0 g/week respectively. In the genetic analysis, the risk of COPD in the C2-C6 groups was similar to that of males in the C1 group. In females, only the C4 group had a lower COPD risk compared to the C1 group (HR=0.79, 95% CI: 0.63-0.99). Conclusion: The study does not support a causal association between alcohol consumption and the risk of COPD.